International registrants should be particularly aware and careful about visa requirements, and should plan travel well in advance. All visa inquiries must be handled by ACM HQ. Please send your request for a letter in support of a visa application to supportletters@acm.org include your name (as it appears on your passport), mailing address, the name of the conference you are attending, and your registration confirmation number. Authors of papers/posters should include the title and indicate whether you are the “sole author” or a “co-author”.